Collecting a gaseous pollutant from air within an animal enclosure

ABSTRACT

An apparatus for collecting a gaseous pollutant from air within a poultry or other concentrated animal feeding enclosure may comprise multiple vertical panel-beds each containing a solid sorbent; a fan to pass the air within the poultry enclosure through the multiple vertical panel-beds and over the solid sorbent; an outlet gate configured to release the solid sorbent from the multiple vertical panel-beds after the fan passes the air over the solid sorbent; a regeneration vessel configured to regenerate the released solid sorbent by recovering the gaseous pollutant from the released solid sorbent; and a conveyor configured to return the regenerated solid sorbent to the multiple vertical panel-beds.

DESCRIPTION OF RELATED ART

The disclosed technology relates to the removal and recovery of gaseouspollutants such as ammonia and/or CO₂, from agriculture facilities toreduce atmospheric emissions and improve indoor air quality.

BACKGROUND

Concentrated animal feeding operations (CAFO) continue to proliferate asthe global demand for low-cost protein increases. Modern advances inCAFO technology have allowed growers to manage a large number of animalson a single farm, which has exacerbated pollutant emissions and theirresulting environmental impact. These operations produce large amountsof pollutants such as hydrogen sulfide, methane, nitrous oxide, carbondioxide, particulate matter, and especially ammonia, which can produceundesirable odors, cause health concerns, and contribute to negativeclimate effects. CAFO's are now the leading cause of ammonia emissionsand have been linked to the degradation of water resources anddetrimental health effects of both animals and human workers. Ammonia isproduced from the microbial decomposition of nitrogen-containing organiccompounds in animal manure and by the hydrolysis of uric acid (Lahav,O., Mor, T., Heber, A. J., Molchanov, S., Ramirez, J. C., Li, C., &Broday, D. M. (2008). A New Approach for Minimizing Ammonia Emissionsfrom Poultry Houses. Water, Air, and Soil Pollution, 191(1-4), 183-197.doi:10.1007/s11270-008-9616-0). Specifically, poultry farming now causesthe most ammonia emissions of any CAFO (30%) (National EmissionInventory-Ammonia Emissions from Animal Husbandry Operations (Rep.),2004, United States Environmental Protection Agency.) These ammoniaemissions are of major environmental concern to the Chesapeake Bay andother waterways. Ammonia's highly soluble nature leads to contaminatedrunoff and over-nitrification of water bodies, which is now severelydegrading water quality and aquatic habitat.

In poultry production, high concentrations of ammonia are linked todecreased bird performance (e.g., reduced bird weight) and healthconcerns (e.g., Newcastle disease and respiratory problems). Studieshave shown that at elevated levels of ammonia of 50 ppm and 75 ppm, birdweight was reduced by 6% and 9%, respectively. Furthermore, ammonialevels above 25 ppm have been linked to increase bird mortality. Inpoultry houses, ammonia concentrations often rise above 50 ppm,especially during low-ventilation periods and when the same litter isutilized for multiple flocks (Miles, D., Branton, S., & Lott, B. (2004).Atmospheric Ammonia is Detrimental to the Performance of ModernCommercial Broilers. Poultry Science, 83(10), 1650-1654.doi:10.1093/ps/83.10.1650). A recent study also examined the same topicand yielded results consistent with the aforementioned study (Zhou etal., 2020, Effects of ammonia exposure on growth performance andcytokines in the serum, trachea, and ileum of broilers. Poultry Science,99(5), 2485-2493. doi:10.1016/j.psj.2019.12.063).

Thus far, ventilation in buildings has been the primary method to reducegaseous pollutant concentrations. However, ventilation rates aredictated by temperature and moisture levels in the building, and not bypollutant levels, meaning pollutant removal is simply a byproduct ofventilation. In the winter and during brooding periods, ventilationrates are lower which leads to increased ammonia concentrations in thebuilding. When unacceptable levels are reached, ventilation rates areincreased to reduce concentrations. However, this causes excessive heatloss and increases heating costs, especially in colder weather.Furthermore, the practice of simply exhausting pollutants negativelyimpacts the environment and contributes to climate change and is,therefore, no longer a desirable practice. A study identified similartrends in the concentrations of other pollutants (i.e., particulatematter, methane, etc.) which have also been linked to detrimental healtheffects in animals and workers. The study suggests filtering pollutantssuch as particulate matter can improve indoor air quality and birdproduction (Wathes, C. M., Holden, M. R., Sneath, R. W., White, R. P., &Phillips, V. R. (1997). Concentrations and emission rates of aerialammonia, nitrous oxide, methane, carbon dioxide, dust and endotoxin inUK broiler and layer houses. British Poultry Science, 38(1), 14-28.doi:10.1080/00071669708417936).

In the U.S., the eight-hour exposure limit to ammonia for humans hasbeen set at 25 ppm by the National Institute of Occupational Safety andHealth, and to 50 ppm by the Occupational Safety and HealthAdministration. However, growers often do not have ammonia monitors todetermine concentrations and instead rely on their senses to determinewhen levels have become unacceptable. However, workers often develop adecreased sensitivity to ammonia levels and become unable to detectammonia until levels are dangerously high (Wheeler, E. E. (2021, July06). Detecting Ammonia in Poultry Housing Using InexpensiveInstruments). Furthermore, the ammonia concentration in poultry houseshas been found to decrease as height from litter increases, and is oftenmuch lower at worker height. This can cause an incorrect sense ofammonia levels by workers at bird level, further driving decreasedproduction performance. In one study that examined ammoniaconcentrations in layer houses, studies found that the ammonia levels atthe surface of the litter were as high as 170 ppm and decreased toambient levels (20 ppm) above 20 cm (bird height) (Lahav, O., Mor, T.,Heber, A. J., Molchanov, S., Ramirez, J. C., Li, C., & Broday, D. M.(2008). A New Approach for Minimizing Ammonia Emissions from PoultryHouses. Water, Air, and Soil Pollution, 191(1-4), 183-197.doi:10.1007/s11270-008-9616-0). In broiler houses, a study found thatconcentrations at the surface of new litter were more than double ofthose at the height of the workers. This same study also found thatammonia concentrations on built-up litters were over double of those onbrand-new litters (Miles, D. (2008). Vertical Stratification of Ammoniain a Broiler House. Journal of Applied Poultry Research, 17(3), 348-353.doi:10.3382/japr.2007-00113). A third study validated this profile inbroiler houses and found rapidly decreasing ammonia concentrations abovebird height (Krause, K. H., & Janssen, J. (n.d.). Measuring andsimulation of the distribution of ammonia in animal houses). Thesestudies have reinforced that although indoor concentrations may beacceptable near the height of the worker, the concentration at theheight of the birds is often much higher and can drive decreased birdperformance.

Traditional ventilation systems are not focused on gaseous pollutantremoval, e.g., for ammonia. As previously mentioned, traditionalpollutant removal occurs in conjunction with ventilation, initiated bytemperature limits. Therefore, their main purpose is not on reducingpollutant concentrations which can cause a buildup of pollutants,especially with reused litter and lower ventilation periods found duringbrooding and cooler weather.

Existing technologies that attempt to solve this issue includebiofilters, biotrickling filters, acid scrubbers, litter additives, abubble column reactor, and a passive permeable membrane system.

Biofilters utilize packed, porous beds of an organic medium, such ascompost, which are immobilized on a metal sieve. The flue gas is passedthrough the packed bed where nitrifying microorganisms on the materialconvert the ammonia to harmless nitrates. The system utilizes theexisting ventilation fans and solely treats exhausted emissions, whichmeans ammonia capture is reduced during low ventilation periods and thesystem cannot improve indoor air quality. Their performance highlydepends on residence times within the material, maintenance of themicroorganisms, and control of moisture levels. They often experiencedegraded performance with high ammonia and dust levels which are foundwith poultry houses. Biofilters are typically not considered viable forlong-term filtration needs due to rapid microorganism exhaustion frompollutant concentrations found in poultry production. They also requirea high material surface area to air flow, necessitating a largeequipment requirement (Melse, Ogink, & Rulkens, W. H. (2009). AirTreatment Techniques for Abatement of Emissions from Intensive LivestockProduction. The Open Agriculture Journal, 3, 6-12).

Biotrickling filters use a similar operating method as biofilters,namely nitrification of ammonia, but utilize an acidic trickle of waterto increase performance. They are able to maintain higher efficienciesthan biofilters, but also require long residence times which driveslarge equipment requirements. The filters are susceptible to the sameclogging and performance degradations found with traditional biofilters,providing challenges with their use in poultry houses. Finally, pressuredrop can increase up to 70 Pa during operations which is too great fortraditional ventilation fans, thus necessitating the replacement ofexisting ventilation fans (Lahav, O., Mor, T., Heber, A. J., Molchanov,S., Ramirez, J. C., Li, C., & Broday, D. M. (2008). A New Approach forMinimizing Ammonia Emissions from Poultry Houses. Water, Air, and SoilPollution, 191(1-4), 183-197. doi:10.1007/s11270-008-9616-0). Likebiofilters, biotricklers depend upon the existing ventilationinfrastructure and are unable to affect the indoor air quality or filterammonia when ventilation fans are not running.

Acid scrubbers utilize a tower packed with organic media that relies onwater sprayed from the top with a low pH (<4) to cross-current orcounter-contact the flue gas. The large amount of contact between theaqueous and gaseous fluids results in filtration of the pollutant. Thedevice relies on the utilization of existing ventilation fans and mustutilize a large contact area to maintain a low pressure drop to preventadditional energy use or require installation of additional fans.Byproducts of the system include concentrated ammonium salt andwastewater, which often require disposal. Variation in performance isexperienced during high ventilation periods (superficial velocity isincreased above 1.5 m/s) and when concentrations are high, which causesnon-consistent performance. Furthermore, there is a large equipment costdue to the high surface area of packing material necessary to maintainresidence time and low pressure drops (Lahav, O., Mor, T., Heber, A. J.,Molchanov, S., Ramirez, J. C., Li, C., & Broday, D. M. (2008). A NewApproach for Minimizing Ammonia Emissions from Poultry Houses. Water,Air, and Soil Pollution, 191(1-4), 183-197.doi:10.1007/s11270-008-9616-0).

Litter additives to include chemical and microbial additives such assodium bisulfate and aluminum sulfate can be added to the litter toeither prevent ammonia formation or by neutralizing the ammonia throughacidification. Performance is initially high (^(˜)75%) and then declinesthroughout the end of the cycle as the additive is used up. Additivesmust be continually added to maintain a high efficiency, but theyprovide diminishing returns since continual addition of additives arenot possible during crops and are consumed at varying rates due to thevariability in ammonia formation (Moore, P., Miles, D., & Burns, R.(2008). Reducing Ammonia Emissions from Poultry Litter with Alum.Mitigating Air Emissions from Animal Feeding Operations).

Another technique involves a bubble column reactor that utilizes anacidic solution to selectively target the air volume near the birdheight. Air flow is provided to the reactor, containing a low pH acidsolution, at a superficial velocity<0.04 m/s. Efficiency is near 100% atthis flow velocity and requires replacement of the acid once exhausted.The reactor utilizes a separate ventilation system to decouple itsoperation from the main ventilation system to maintain low ammoniaconcentrations within the house. This technique allows for a decreasedsystem size due to the smaller volumetric flow rate, however, the lowsuperficial velocity still drives a large equipment size causing asignificant challenge to its economic attractiveness (Lahav, O., Mor,T., Heber, A. J., Molchanov, S., Ramirez, J. C., Li, C., & Broday, D. M.(2008). A New Approach for Minimizing Ammonia Emissions from PoultryHouses. Water, Air, and Soil Pollution, 191(1-4), 183-197.doi:10.1007/s11270-008-9616-0).

Another technique is the use of a microporous, hydrophobic, gaspermeable membrane. The system is a passive system that pumps acidthrough tubing located near the height of the birds. Ammonia is allowedto pass through the membrane where it is then collected in aconcentrated ammonium salt. It does not require any air flow handlingand is thus able to reduce electricity costs (Szogi, A. A., Vanotti, M.B., & Rothrock, M. J. (2014). U.S. Pat. No. 8,906,332 B2. Washington,D.C.: U.S. Patent and Trademark Office.).

For at least these reasons, many problems and shortcomings exist withknown technologies and processes.

SUMMARY

Some aspects of the invention relate to providing a system and methodfor overcoming some or a set of the problems set forth abovesimultaneously.

According to one aspect of some embodiments, the system and methodprovide for the filtration of one or more gaseous or solid pollutants(e.g., ammonia) from an agriculture (or other) facility, through the useof solid sorbents.

According to one aspect of some embodiments, the system and method areconfigured to both reduce atmospheric emissions from CAFOs and improvethe indoor air quality of such operations to improve the health andperformance of animals and the working environments for humans. Multiplesystems can be integrated to filter any number of pollutants.

According to one aspect of some embodiments, the system and methodinvolve use of a panel-bed system that utilizes solid adsorbentsspecifically chosen for their selectivity toward the desired pollutant(e.g., ammonia). The sorbents are arranged in vertical beds that arearranged horizontally to provide a compact footprint. High mass transferrates found with sorbents allow for equipment size to be minimized. Thesorbent is able to filter the pollutant when contacted with the flue gasdescribed by physisorption and chemisorption principles. The sorbentsare placed in thin beds to minimize the pressure drop and resultingelectricity costs.

According to one aspect of some embodiments, the system and methodinvolves the use of a customizable duct system, either indoor, outdoor,or a combination, to draw in air, independent of the main ventilationsystem, to deliver the air to the panel-bed for filtration of thepollutant from the air stream. Air is either recirculated into thestructure or exhausted to the ambient environment.

According to one aspect of some embodiments, the system and methodinvolve use of the targeted filtration of air inside the structure andindependent of the main ventilation system, such that the indoor airquality can be improved to increase the animal performance. This alsoreduces the atmospheric emissions and reduces the environmentalfootprint of such operations.

According to one aspect of some embodiments, the system and method isconfigured and operable to produce a useable byproduct utilizing thecaptured pollutant to offset the cost of capture and increase theefficiency of the system.

According to another aspect of some embodiments, the system and methodare configured and operable to provide a gaseous pollutant (e.g.,ammonia) removal filtration device independent of the traditional (e.g.,animal house) ventilation system to control emissions and simultaneouslyimprove the health and wellbeing of workers and birds. The reduction ofemissions can improve natural resources, prevent small particulateformation, and improve health and societal CAFO tolerance of localpopulaces. Such an approach can increase the weight and production ofbroilers, layers, and other animals to improve the economics of CAFOs.Additionally, the system may be located close to the surface of thelitter and the origin of ammonia production to minimize the volumetricflow requirement and, therefore, the overall system size by targetingthis air volume.

In contrast to some prior system, the various aspects of the disclosedsystem and method can simultaneously achieve multiple design goals andsolve combinations of problems, including various permutations of theproblems set forth above. The unique configuration and operation of thesystems and methods described herein provides synergistic results notheretofore seen with prior systems.

For simplicity, various examples are provided in connection with ammoniacapture from poultry CAFOs where the system can be coupled with aparticulate matter filter device to reduce particulates for furtheremissions control and improved animal health. The invention is notlimited to this specific example. The technology described herein can beused in other facilities and/or for other pollutants.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure, in accordance with one or more variousembodiments, is described in detail with reference to the followingfigures. The figures are provided for purposes of illustration only andmerely depict typical or example embodiments.

FIG. 1 is a block system diagram of a panel-bed pollutant capture systemaccording to some embodiments of the disclosed technologies.

FIG. 2 depicts a complete filtration system according to someembodiments of the disclosed technologies.

FIG. 3 shows a panel-bed filter according to some embodiments of thedisclosed technologies.

FIG. 4 provides an example duct pipe that may be placed inside an animalhouse for the targeted capture of a specific air volume.

FIG. 5 is a flowchart illustrating a process for collecting a gaseouspollutant from air within an animal enclosure.

FIG. 6 is an example computing component that may be used to implementvarious features of embodiments described in the present disclosure.

The figures are not exhaustive and do not limit the present disclosureto the precise form disclosed.

DETAILED DESCRIPTION

Embodiments of the disclosure provide systems and methods for thecapture of gaseous and/or solid pollutants from an enclosed area. Thegaseous pollutants may include ammonia, carbon dioxide, and similargaseous pollutants. Solid pollutants may include any size of particulatematter. The source of the pollutants may be within the enclosed area.The source of the pollutants may be waste from concentrated feedinganimal operations or other sources. In this disclosure, the animals aresometimes described as poultry. However, is should be understood thatthe disclosed technologies apply to animals other than poultry as well.

The system may collect polluted air through one or more air filtrationdevices, such as a series of ducts for filtration in a panel-bed devicethat may use solid sorbents placed in vertical beds arrangedhorizontally in a compact system. Each panel consists of two meshscreens that are separated by a distance equivalent to the desiredsorbent bed depth, typically less than one inch. Each mesh is supportedby a rectangular frame that is used to provide structure and tension tothe mesh. The mesh forms the filtration area of the unit and permits airto pass through the system and contact the sorbent to effect filtration.The sorbents are placed in the middle of each panel and are deliveredfrom the top of the unit and expulsed at the bottom. Together, thesorbent and panel form the panel-bed. Each vertical panel is placed intothe main chassis, and additional panels are arranged horizontally toscale the unit to the required capacity. The total surface area of thecontact side of the panels is directly proportional to the volumetricflow capacity of the system. Each panel is segregated from the others bynon-porous barriers on either side to form a panel-bed chamber, so aircan be uniformly distributed across each panel. The air manifold isdesigned to deliver and remove uniformly distributed air to eachpanel-bed chamber for even saturation and efficient system operations.The collected pollutant may be recovered from the solid sorbents througha regeneration device that utilizes one or more recovery processes. Therecovery process may include heat, pressure changes, fluid wash, andsimilar processes. The pollutant may be recovered in a gaseous or liquidform. The pollutant may be recovered in a manner that allows the reuseof the pollutant.

The solid sorbents may include zeolites, activated carbon, ion exchangeresins, metal organic frameworks (MOFs), Prussian blue, and/or othersolid sorbents. The gaseous pollutants may include any material orcompound that can be adsorbed by sorbents.

The system may include multiple panel-beds of different sorbents for theremoval of multiple pollutants. The system may be coupled with aparticulate matter filter device to reduce particulates for furtheremissions control and improved animal health.

The disclosed technologies may employ a panel-bed filtration system thatutilizes thin vertical beds of solid sorbents. The sorbent beds may bethin, for example less than two inches in thickness, and typically lessthan one inch. Other thicknesses may be used. The thickness may beselected according to the characteristics of the sorbent employed. Thethin sorbent bed depths allow for a short flow path which minimizes thepressure drop and required energy for system operations. Thehorizontally arranged vertical beds permit a small footprint to bemaintained and for equipment sizes and capital costs to be minimized.Bed thickness selection is dependent on the adsorption equilibriumcapacity of each sorbent at the pollutant partial pressure found withinthe flue gas. This instantaneous pollutant concentration directlycorresponds to a capacity of that pollutant in the sorbent, and thecapacity can change due to any number of factors including temperature,humidity, variation in pollutant partial pressures, and competingpollutants. The resulting capacity and pollutant concentration resultsin a specific saturation time in which the sorbents will need to bereplaced. Utilizing these respective sorbent characteristics, the beddepth can be selected for the employed sorbent to achieve the desiredprocess characteristics and performance, such as cycle time.Furthermore, factors such as superficial flow velocity and sorbent masstransfer limitations can affect the mass flow rate of pollutants, thecapture efficiency, cycle time, and other process characteristics andmust be accounted for when determining bed thickness. Optimizing thesecharacteristics ensures an efficient system as together, the sorbent'scapabilities, resulting air flow velocity, and total availablefiltration area provided by the panels affect the total size andperformance of the device.

The system may draw in air from ventilation ducts placed at appropriateelevations throughout a broiler, layer, or other poultry facility. Forexample, the ducts may be placed along the feeder lines in a broilerhouse. The ducts may be customized to the specific needs of the facilityand may also be placed outside of the building if needed. Air may bedrawn into a central duct, e.g., via a high flow rate fan that leads tothe panel-bed filter. The air flow rate may be approximately 10% of thehouse volume per minute. However, volumetric flow may be increased byadding additional panels to handle the desired air volume. An airmanifold may receive and distribute the air flow among the enclosed andsegregated vertical panel-beds to uniformly saturate the sorbent beds.The panel-bed may have a number of vertical panel-beds whose quantity isdependent on the size of the house, the resulting air flow requirement,and the desired superficial velocity. Superficial velocity is determinedbased upon the pollutant mass transfer rate of the sorbent. Each sorbenthas a corresponding pollutant mass transfer rate limitation, and thisrate can be affected by a number of factors (humidity, temperature,competing pollutants, etc.). The flue gas will have a varying mass flowrate based upon pollutant formation rates, resulting animal structureconcentrations, and volumetric flow velocity. The superficial flowvelocity is selected based upon ensuring the mass flow rate does notexceed the mass transfer rate of the sorbent so a high captureefficiency can be maintained throughout filtration. Other factors thatcan affect the selected superficial flow velocity may include sorbentbed thickness, equipment costs, equipment limitations, and pressure droplimitations.

Superficial air velocity is dependent on the characteristics of thesorbent and can commonly range between 0.1 m/s to 2.0 m/s. The flue gasmay pass through each sorbent bed where it contacts the solid sorbentand the desired pollutant is adsorbed to effect filtration, for examplethrough physisorption and/or chemisorption. The flue gas may be filteredwith high efficiency, up to 100%, with minimal residence times beforeexiting the panel-bed. During cold weather, the air may be recycled backto the structure to minimize heat loss and reduce propane heating costs.In the summer, the air may be vented to provide additional ventilationcapacity.

The filtration system may be decoupled from the main ventilation systemto improve the indoor air quality near the animals for increasedproduction performance while simultaneously reducing emissions. Thesystem may utilize a dedicated fan to either continuously orintermittently filter the air. The fan may be triggered when pollutantlevels exceed a desired threshold.

When the sorbent is sufficiently saturated with the adsorbate (that is,saturated to a desired degree), gates may open at the bottom of the unitand the sorbent may be expulsed into a sorbent collection bin at thebottom of the panel-beds. The gate may then close, and a gate at the topof the panel-bed may open to allow fresh sorbent to flow into the panelswhere filtration is allowed to resume. In various embodiments, thesystem may employ any combination of top or bottom gate, or use none atall.

The expulsed sorbent may be directed into a sorbent regenerationchamber. For certain sorbents (i.e., activated carbons, zeolites, MOFs,etc.) the sorbent may be directed to a bulk solids heat exchanger orother heating element or process, coupled with a vacuum pump in somecircumstances, where heat sufficient for the specific sorbent is appliedto decrease the adsorption equilibrium causing the adsorbate to desorb.A vacuum pump may operate to pull a vacuum to assist with desorptionand/or recover the gaseous pollutant. A thermal fluid such as steam orthermal oil may be heated and used in the bulk solids heat exchanger.The recovered gaseous pollutant may then pass through a condenser, ifneeded, to reduce water content and then may be stored in a gaseous orliquid form. After desorption is sufficient, the sorbent may be moved tothe top of the panel-bed by a conveyor where it may be allowed to cooluntil needed for adsorption once again. The conveyor may be pneumatic ormechanical. With sorbents such as Prussian blue analogues, theregeneration device may be a water jet system where sufficient water isutilized to wash the sorbent and recover the adsorbate in an aqueousform. The recovered pollutant may be sold for industry use or utilizedto offset costs. For example, ammonium hydroxide may be used asfertilizer, and ammonia gas may be used as an alternative fuel source.

The disclosed technologies may utilize solid sorbents which have beenshown to maintain high capture efficiencies until breakthrough, even atlow ammonia concentrations (<10 ppm), and can be continually regeneratedand reused to lower operations costs (Takahashi, A., Minami, K., Noda,K., Sakurai, K., & Kawamoto, T. (2020). Trace Ammonia Removal from Airby Selective Adsorbents Reusable with Water. ACS Applied Materials &Interfaces, 12(13), 15115-15119. doi:10.1021/acsami.9b22384).

FIG. 1 is a block system diagram of a panel-bed pollutant capture systemaccording to some embodiments of the disclosed technologies. Whileembodiments of the disclosed pollutant capture systems are described interms of poultry farming, it should be understood that embodiments ofthe disclosed pollutant capture systems may have other applications,both in other farming operations and in non-farming operations.

Referring to FIG. 1, a panel-bed air filtration device 1 may receiveflue gas 2 from the animal house 8 where it may pass through one or moresorbent beds within the filtration device 1. The filtration system maycapture one or more pollutants from the flue gas. At 3, the filteredflue gas may be recirculated to the animal house, exhausted outside theanimal house, or a combination thereof. After the sorbents are saturatedwith the pollutant(s), they may be dropped into a regeneration vessel 4.A fluid 5 may be used to recover the pollutant(s). In some embodiments,thermal fluid may be used to regenerate the sorbent through heating, forexample via a heat exchanger. In some embodiments, water may be sprayedinto the tank to regenerate the sorbent. The recovered pollutant 6 maybe removed from the regeneration vessel 4. A vacuum pump may be used toremove gaseous pollutants. A water pump may be used to remove aqueouspollutants. For particulate matter filtration, the device could be Afterregeneration, the regenerated sorbent 7 may be conveyed to the top ofthe panel-bed for reuse.

FIG. 2 depicts a complete filtration system according to someembodiments of the disclosed technologies. Ventilation air ducts 9 maybe placed within the enclosed area of the animal house 8 at the sameelevation as the animals. The ducts 9 may be attached to otherstructures, for example such as the feeding lines. A fan or blower 10may draw in polluted air from the ducts, and may deliver the air to anoptional particulate matter filtration device 11. The optionalparticulate matter filtration device 11 may be a bag filter, cartridgefilter, or a similar device. The particulate matter filtration devicemay also be a panel-bed device that uses a sorbent, such as a silica, toeffect capture of all particulate sizes. A particulate matterregeneration device such as a fluidized bed may be used to separate thesorbent from the particulate matter. The air may then be passed througha panel-bed pollutant capture device 12 where the pollutant may befiltered and recovered. The panel-bed pollutant capture device 12 may beimplemented as shown in FIG. 1. The filtered air may then be may berecirculated to the animal house, exhausted outside the animal house, ora combination thereof, by a switching valve 13. A pollutant sensor 25may be disposed within the animal house 8 at the same elevation as theanimals. The fan or blower 10 may be triggered when readings from thesensor 25 exceed a threshold.

FIG. 3 shows a panel-bed filter according to some embodiments of thedisclosed technologies. Flue gas may enter an inlet pipe 15, and may bedistributed equally within an inlet manifold 16. Each portion of theinlet manifold 16 may distribute the flue gas to a respective enclosedpanel-bed chamber 23. Within each panel-bed chamber 23, the flue gas maypass through a respective panel-bed 17. Each panel-bed 17 may containsold sorbent (not shown). In some embodiments, each panel-bed 17 may beless than 1 inch thick. Each panel-bed 17 may be enclosed by barriers18, 19 on both sides to segregate the distributed air flow amongst allpanel-beds. For example, each panel-bed 17 may be enclosed on both sidesby a non-porous sheet or a similar device to form the panel-bed chambers23. The flue gas may be distributed along the entire length of thepanel-bed chamber 23 to promote uniform saturation of the solid sorbent.The filtered gas may exit each panel-bed 17 through outlet manifolds(not shown) and an outlet pipe 14. The outlet manifolds may beimplemented in a manner similar to that of the inlet manifolds 16.

When the sorbents are saturated, a gate 24 at the bottom of thepanel-bed filter may open to allow the saturated sorbent to fall intothe collection chamber 22. The gate 24 may be closed, and a similar gate24 at the top of the panel-bed filter may be opened to allow freshsorbent to fill the panel-beds 17 from a sorbent storage area 21. Thegates 24 may be operated via actuators 20. The saturated sorbents maythen be sent from the collection chamber 22 to a regeneration section(not shown) to desorb and recover the pollutant. Regenerated sorbent maybe conveyed to the sorbent storage area 21.

In the embodiment of FIG. 3, the vertical panel-beds 17 are arrangedhorizontally, and gravity alone may be sufficient to remove thesaturated sorbents from the panel-beds 17. In other embodiments, thepanel-beds 17 may be non-vertical and arranged in a non-horizontalmanner. In any embodiment, a scraper may be used to effect the removalof the saturated sorbents from the panel-beds 17.

FIG. 4 provides an example duct pipe 27 that may be placed inside ananimal house for the targeted capture of a specific air volume. The ductpipe 27 may be attached to the feeding lines in a animal house via abracket 25. Couplings 26 may serve as duct inlets. Each coupling 26 mayhave a screen 28 to prevent large particulate matter from entering theduct inlet.

FIG. 5 is a flowchart illustrating a process 500 for collecting agaseous pollutant from air within a poultry enclosure. The elements ofthe process 500 are presented in one arrangement. However, it should beunderstood that one or more elements of the process may be performed ina different order, in parallel, omitted entirely, and the like.Furthermore, the process 500 may include other elements in addition tothose presented.

Referring to FIG. 5, the process 500 may include passing air within theanimal enclosure into multiple vertical panel-beds and over solidsorbent contained within the vertical panel-beds, at 502. For example,the blower 10 of FIG. 2 may pass air within the animal enclosure 8 intothe multiple vertical panel-beds 17 of FIG. 3 and over the solid sorbentcontained within the vertical panel-beds 17.

Referring again to FIG. 5, the process 500 may include releasing thesolid sorbent from the multiple vertical panel-beds after passing theair within the animal enclosure into the multiple vertical panel-bedsand over the solid sorbent contained within the vertical panel-beds, at504. For example, referring again to FIG. 3, the actuator 20 may operatethe outlet gate 24 to release the solid sorbent from the multiplevertical panel-beds 17 into the collection chamber 22.

Referring again to FIG. 5, the process 500 may include regenerating thereleased solid sorbent by recovering the gaseous pollutant from thereleased solid sorbent, at 508. For example, the released solid sorbentmay be conveyed from the collection chamber 22 of FIG. 3 to theregeneration vessel 4 of FIG. 1. The solid sorbent may be regenerated asdescribed above, and the recovered gaseous pollutant may be collected,as shown at 6 in FIG. 1.

Referring again to FIG. 5, the process 500 may include returning theregenerated solid sorbent to the multiple vertical panel-beds, at 510.For example, referring again to FIG. 1, the regenerated solid sorbentmay be conveyed from the regeneration vessel 4 to the panel-bed airfiltration device 1. Referring again to FIG. 3, the regenerated solidsorbent may be conveyed to the sorbent storage area 21. The actuator 20may operate the inlet gate 24 to release the solid sorbent into themultiple vertical panel-beds 17 from the sorbent storage area 21 intothe collection chamber 22.

Embodiments of the disclosed technologies may be implemented to provideadvantages over conventional solutions. The disclosed technologies bothreduce atmospheric emissions from CAFOs, and improve the indoor airquality of such operations to improve the health and performance ofanimals and the working environments for humans. The arrangement of thesorbents in vertical beds that are horizontally stacked provide acompact footprint, for example having sizes magnitudes smaller thantraditional technologies. The sorbents may be placed in thin beds tominimize the pressure drop and resulting electricity costs. Thecustomizable duct system may be independent of the main ventilationsystem to provide a dedicated system for the removal of pollutants, andso air may be recirculated into the structure, exhausted to the ambientenvironment, or both. The system may produce a useable byproductutilizing the captured pollutant, which may offset the cost of captureand increase the economics of the system.

In some embodiments, the operation of the disclosed systems may becontrolled by a computer system. FIG. 6 depicts a block diagram of anexample computer system 600 in which embodiments described herein may beimplemented. The computer system 600 includes a bus 602 or othercommunication mechanism for communicating information, one or morehardware processors 604 coupled with bus 602 for processing information.Hardware processor(s) 604 may be, for example, one or more generalpurpose microprocessors.

The computer system 600 also includes a main memory 606, such as arandom access memory (RAM), cache and/or other dynamic storage devices,coupled to bus 602 for storing information and instructions to beexecuted by processor 604. Main memory 606 also may be used for storingtemporary variables or other intermediate information during executionof instructions to be executed by processor 604. Such instructions, whenstored in storage media accessible to processor 604, render computersystem 600 into a special-purpose machine that is customized to performthe operations specified in the instructions.

The computer system 600 further includes a read only memory (ROM) 608 orother static storage device coupled to bus 602 for storing staticinformation and instructions for processor 604. A storage device 610,such as a magnetic disk, optical disk, or USB thumb drive (Flash drive),etc., is provided and coupled to bus 602 for storing information andinstructions.

The computer system 600 may be coupled via bus 602 to a display 612,such as a liquid crystal display (LCD) (or touch screen), for displayinginformation to a computer user. An input device 614, includingalphanumeric and other keys, is coupled to bus 602 for communicatinginformation and command selections to processor 604. Another type ofuser input device is cursor control 616, such as a mouse, a trackball,or cursor direction keys for communicating direction information andcommand selections to processor 604 and for controlling cursor movementon display 612. In some embodiments, the same direction information andcommand selections as cursor control may be implemented via receivingtouches on a touch screen without a cursor.

The computing system 600 may include a user interface module toimplement a GUI that may be stored in a mass storage device asexecutable software codes that are executed by the computing device(s).This and other modules may include, by way of example, components, suchas software components, object-oriented software components, classcomponents and task components, processes, functions, attributes,procedures, subroutines, segments of program code, drivers, firmware,microcode, circuitry, data, databases, data structures, tables, arrays,and variables.

In general, the word “component,” “engine,” “system,” “database,” datastore,” and the like, as used herein, can refer to logic embodied inhardware or firmware, or to a collection of software instructions,possibly having entry and exit points, written in a programminglanguage, such as, for example, Java, C or C++. A software component maybe compiled and linked into an executable program, installed in adynamic link library, or may be written in an interpreted programminglanguage such as, for example, BASIC, Perl, or Python. It will beappreciated that software components may be callable from othercomponents or from themselves, and/or may be invoked in response todetected events or interrupts. Software components configured forexecution on computing devices may be provided on a computer readablemedium, such as a compact disc, digital video disc, flash drive,magnetic disc, or any other tangible medium, or as a digital download(and may be originally stored in a compressed or installable format thatrequires installation, decompression or decryption prior to execution).Such software code may be stored, partially or fully, on a memory deviceof the executing computing device, for execution by the computingdevice. Software instructions may be embedded in firmware, such as anEPROM. It will be further appreciated that hardware components may becomprised of connected logic units, such as gates and flip-flops, and/ormay be comprised of programmable units, such as programmable gate arraysor processors.

The computer system 600 may implement the techniques described hereinusing customized hard-wired logic, one or more ASICs or FPGAs, firmwareand/or program logic which in combination with the computer systemcauses or programs computer system 600 to be a special-purpose machine.According to one embodiment, the techniques herein are performed bycomputer system 600 in response to processor(s) 604 executing one ormore sequences of one or more instructions contained in main memory 606.Such instructions may be read into main memory 606 from another storagemedium, such as storage device 610. Execution of the sequences ofinstructions contained in main memory 606 causes processor(s) 604 toperform the process steps described herein. In alternative embodiments,hard-wired circuitry may be used in place of or in combination withsoftware instructions.

The term “non-transitory media,” and similar terms, as used hereinrefers to any media that store data and/or instructions that cause amachine to operate in a specific fashion. Such non-transitory media maycomprise non-volatile media and/or volatile media. Non-volatile mediaincludes, for example, optical or magnetic disks, such as storage device610. Volatile media includes dynamic memory, such as main memory 606.Common forms of non-transitory media include, for example, a floppydisk, a flexible disk, hard disk, solid state drive, magnetic tape, orany other magnetic data storage medium, a CD-ROM, any other optical datastorage medium, any physical medium with patterns of holes, a RAM, aPROM, and EPROM, a FLASH-EPROM, NVRAM, any other memory chip orcartridge, and networked versions of the same.

Non-transitory media is distinct from but may be used in conjunctionwith transmission media. Transmission media participates in transferringinformation between non-transitory media. For example, transmissionmedia includes coaxial cables, copper wire and fiber optics, includingthe wires that comprise bus 602. Transmission media can also take theform of acoustic or light waves, such as those generated duringradio-wave and infra-red data communications.

The computer system 600 also includes a communication interface 618coupled to bus 602. Network interface 618 provides a two-way datacommunication coupling to one or more network links that are connectedto one or more local networks. For example, communication interface 618may be an integrated services digital network (ISDN) card, cable modem,satellite modem, or a modem to provide a data communication connectionto a corresponding type of telephone line. As another example, networkinterface 618 may be a local area network (LAN) card to provide a datacommunication connection to a compatible LAN (or a WAN component tocommunicate with a WAN). Wireless links may also be implemented. In anysuch implementation, network interface 618 sends and receiveselectrical, electromagnetic or optical signals that carry digital datastreams representing various types of information.

A network link typically provides data communication through one or morenetworks to other data devices. For example, a network link may providea connection through local network to a host computer or to dataequipment operated by an Internet Service Provider (ISP). The ISP inturn provides data communication services through the world wide packetdata communication network now commonly referred to as the “Internet.”Local network and Internet both use electrical, electromagnetic oroptical signals that carry digital data streams. The signals through thevarious networks and the signals on network link and throughcommunication interface 618, which carry the digital data to and fromcomputer system 600, are example forms of transmission media.

The computer system 600 can send messages and receive data, includingprogram code, through the network(s), network link and communicationinterface 618. In the Internet example, a server might transmit arequested code for an application program through the Internet, the ISP,the local network and the communication interface 618.

The received code may be executed by processor 604 as it is received,and/or stored in storage device 610, or other non-volatile storage forlater execution.

Each of the processes, methods, and algorithms described in thepreceding sections may be embodied in, and fully or partially automatedby, code components executed by one or more computer systems or computerprocessors comprising computer hardware. The one or more computersystems or computer processors may also operate to support performanceof the relevant operations in a “cloud computing” environment or as a“software as a service” (SaaS). The processes and algorithms may beimplemented partially or wholly in application-specific circuitry. Thevarious features and processes described above may be used independentlyof one another, or may be combined in various ways. Differentcombinations and sub-combinations are intended to fall within the scopeof this disclosure, and certain method or process blocks may be omittedin some implementations. The methods and processes described herein arealso not limited to any particular sequence, and the blocks or statesrelating thereto can be performed in other sequences that areappropriate, or may be performed in parallel, or in some other manner.Blocks or states may be added to or removed from the disclosed exampleembodiments. The performance of certain of the operations or processesmay be distributed among computer systems or computers processors, notonly residing within a single machine, but deployed across a number ofmachines.

As used herein, a circuit might be implemented utilizing any form ofhardware, or a combination of hardware and software. For example, one ormore processors, controllers, ASICs, PLAs, PALs, CPLDs, FPGAs, logicalcomponents, software routines or other mechanisms might be implementedto make up a circuit. In implementation, the various circuits describedherein might be implemented as discrete circuits or the functions andfeatures described can be shared in part or in total among one or morecircuits. Even though various features or elements of functionality maybe individually described or claimed as separate circuits, thesefeatures and functionality can be shared among one or more commoncircuits, and such description shall not require or imply that separatecircuits are required to implement such features or functionality. Wherea circuit is implemented in whole or in part using software, suchsoftware can be implemented to operate with a computing or processingsystem capable of carrying out the functionality described with respectthereto, such as computer system 600.

As used herein, the term “or” may be construed in either an inclusive orexclusive sense. Moreover, the description of resources, operations, orstructures in the singular shall not be read to exclude the plural.Conditional language, such as, among others, “can,” “could,” “might,” or“may,” unless specifically stated otherwise, or otherwise understoodwithin the context as used, is generally intended to convey that certainembodiments include, while other embodiments do not include, certainfeatures, elements and/or steps.

Terms and phrases used in this document, and variations thereof, unlessotherwise expressly stated, should be construed as open ended as opposedto limiting. Adjectives such as “conventional,” “traditional,” “normal,”“standard,” “known,” and terms of similar meaning should not beconstrued as limiting the item described to a given time period or to anitem available as of a given time, but instead should be read toencompass conventional, traditional, normal, or standard technologiesthat may be available or known now or at any time in the future. Thepresence of broadening words and phrases such as “one or more,” “atleast,” “but not limited to” or other like phrases in some instancesshall not be read to mean that the narrower case is intended or requiredin instances where such broadening phrases may be absent.

What is claimed is:
 1. An apparatus for collecting a gaseous pollutantfrom air within an animal enclosure, the apparatus comprising: multiplevertical panel-beds each containing a solid sorbent; a duct having aduct inlet in fluid communication with the air within the animalenclosure; an inlet manifold, wherein the inlet manifold is in fluidcommunication with the duct and the multiple vertical panel-beds; a fanconfigured to pass the air within the animal enclosure through the ductand the inlet manifold into the multiple vertical panel-beds and overthe solid sorbent; an outlet gate configured to release the solidsorbent from the multiple vertical panel-beds after the fan passes theair within the animal enclosure through the duct and the inlet manifoldinto the multiple vertical panel-bed chambers and over the solidsorbent; a regeneration vessel configured to regenerate the releasedsolid sorbent by recovering the gaseous pollutant from the releasedsolid sorbent; and a conveyor configured to return the regenerated solidsorbent to the multiple vertical panel-beds.
 2. The apparatus of claim1, wherein the solid sorbent comprises at least one of: a zeolite;activated carbon; an ion exchange resins; a metal organic framework;silica; polymers; amine functionalized sorbent variations; Prussianblue; and other natural organic, inorganic, or synthetic sorbents. 3.The apparatus of claim 1, wherein the gaseous pollutant comprises atleast one of: ammonia; methane; hydrogen sulfide; nitrous oxides; carbonmonoxide; and carbon dioxide.
 4. The apparatus of claim 1, wherein eachof the multiple panel-beds comprises: a porous sheet configured tocontain the solid sorbent and non-porous sheets to enclose the verticalpanel-beds.
 5. The apparatus of claim 1, further comprising: an actuatorconfigured to operate the outlet gate.
 6. The apparatus of claim 1,further comprising: a collection chamber configured to hold the solidsorbent after release of the solid sorbent from the multiple panel-beds.7. The apparatus of claim 1, further comprising: a sorbent storage areaconfigured to hold the solid sorbent after transfer of the solid sorbentfrom the regeneration vessel; and an inlet gate configured to releasethe solid sorbent from the sorbent storage area into the multiplevertical panel-beds.
 8. The apparatus of claim 7, further comprising: anactuator configured to operate the inlet gate.
 9. The apparatus of claim1, further comprising: a structure configured to hold the duct inlet ata same elevation as an animal within the animal enclosure.
 10. Theapparatus of claim 1, further comprising: a particulate matterfiltration device configured to filter particulates from the air priorto the air passing over the solid sorbent.
 11. The apparatus of claim 1,further comprising: a scraper configured to effect the removal of thesorbent from the multiple panel-beds.
 12. The apparatus of claim 1,further comprising: a screen configured to prevent large particulatematter from entering the duct.
 13. The apparatus of claim 1, wherein:wherein two or more of the vertical panel-beds contain different solidsorbents to adsorb different gaseous pollutants.
 14. A method forcollecting a gaseous pollutant from air within an animal enclosure, themethod comprising: passing the air within the animal enclosure intomultiple vertical panel-beds and over solid sorbent contained within thevertical panel-beds; releasing the solid sorbent from the multiplevertical panel-beds after passing the air within the animal enclosureinto the multiple vertical panel-beds and over the solid sorbentcontained within the vertical panel-beds; regenerating the releasedsolid sorbent by recovering the gaseous pollutant from the releasedsolid sorbent; and returning the regenerated solid sorbent to themultiple vertical panel-beds.
 15. The method of claim 14, wherein thesolid sorbent comprises at least one of: a zeolite; activated carbon; anion exchange resins; a metal organic framework; silica; polymers; aminefunctionalized sorbent variations; Prussian blue; and other naturalorganic, inorganic, or synthetic sorbents.
 16. The method of claim 14,wherein the gaseous pollutant comprises at least one of: ammonia;methane; hydrogen sulfide; nitrous oxides; carbon monoxide; and carbondioxide.
 17. The method of claim 14, wherein releasing the solid sorbentfrom the multiple vertical panel-beds comprises: operating an outletgate.
 18. The method of claim 14, further comprising: collecting the airwithin the animal enclosure at a same elevation as an animal within theanimal enclosure prior to passing the air within the animal enclosureinto the multiple vertical panel-beds and over the solid sorbentcontained within the vertical panel-beds.
 19. The method of claim 14,further comprising: filtering particulates from the air within theanimal enclosure prior to passing the air into the multiple verticalpanel-beds and over the solid sorbent contained within the verticalpanel-beds.
 20. The method of claim 14, wherein releasing the solidsorbent from the multiple vertical panel-beds comprises: scraping thesolid sorbent from the multiple panel-beds.
 21. The method of claim 14,further comprising: preventing large particulate matter from reachingthe solid sorbent contained within the vertical panel-beds.
 22. Themethod of claim 14, wherein: wherein two or more of the verticalpanel-beds contain different solid sorbents to adsorb different gaseouspollutants.